Conversely, near infrared (NIR) spectroscopy characterization can differentiate among distinct bands specific to each epoxide, primary amine, phenyl, combined primary-secondary amine, and the resulting hydroxyl groups during cure of epoxy-amine systems [12-19].
The epoxy, primary amine, and secondary amine concentrations were calculated using the integrated area under each respective peak using Lambert-Beer's law while the total amine H concentration was calculated by adding the primary amine H and secondary amine H concentrations from each spectrum.
It is also a primary amine
that is excreted unchanged in the urine.
6 times faster with phenyl glycidyl ether (PGE) than the primary amine
PSAO has high selectivity towards primary amines
and it can be efficiently purified with simple ion exchange and gel permeation chromatographic methods.
Our studies start with a brief examination of the ammonia system before progressing to latent primary amines
The two monoprimary amines--n-amyl and n-dodecyl amine--effect chain extension by simply joining two epoxy resin molecules via the single difunctional primary amine
For kinetic experiments, aniline, N-methyl aniline, and dimethyl aniline, (a primary amine
, a secondary amine, and a tertiary amine) were also obtained from Aldrich.
The Schiff bases formed were reduced to primary amines
with sodium cyanoborohydride, and then the wells were blocked with 1 g/L bovine serum albumin to prevent nonspecific binding.
form an unstable diazonium hydroxide that decomposes to an alcohol and nitrogen, while tertiary amines do not readily form nitrosamines.
react approximately twice as fast as secondary amines, as the overall reaction rate of an amine with an epoxy resin is also influenced by the steric hindrance.
31) For small molecular-mass primary amines
, such as 1,3-bis(aminomethyl)-cyclohexane (1,3 BAC) used in this study, the reaction between amines and carbon dioxide is rapid, and the addition of moisture increases the sorption capacity and the reaction rate.
Nitrosamines from vulcanizing agents can be controlled or eliminated by using only primary amine
based accelerators or accelerators which form stable fragments during cure.